I often want to delete a lot whitespaces between one word and another and had to hit the “Delete” buttons many times. Now I just discovered this command M-^ (delete-indentation &optional arg) works perfectly for my need.

Having my work changed a lot during the last year, from a Lunix developer to a half developer half support and now are purely support, I do not have many chance to use Emacs that often anymore, but I keep to use to it as much as possible. After all it’s my first editor in my programmer career. One thing I like is its shell buffers. Unfortunately, It only support one shell as I thought before. Because if you type M-x shell to open a new shell buffer, if you already have one open that will just switch to the existing one.

What is Regular Expression? A regular expression is a special text string for describing a certain amount of text. Generally, A regular expression contains a few special characters and ordinary characters. If you have used Linux/Windows systems, you will probably familiar with wildcard notations such as *.txt to find all text files in a folder. That’s a simple regular expression example (Thanks for netcasper’s correcting . The regex equivalent to “.txt” is .*.txt). Nowadays, Most of the text editors support regular expression such as vi, emacs and Ultra Editor(not a free software). Today, I would like introduce some basic knowledge about regular expression and use it in Emacs to improve the efficiency of your coding work.